I believe every style listed on this site is a “martial art”. It’s because of that word “art”. “Martial” means that these styles relate to war. “Art” means they’re an interpretation of that which is meaningful, aesthetically pleasing, useful, or significant in some way. Most people here are judging simply on the basis of whether it’s useful, which, one could argue, very few martial arts are any more.

Sumo was once a battle to the death, so surely saying that it is martial would be accurate. And the Japanese seem to find something beautiful to it, however strange that may be, and so it is an art. It also has significant aspects found in few other styles. This is one of the only cases where the combatants collide with directly opposing force, in an attempt to overcome the enemy with the full force of one’s body. Actually, I can actually see some beautiful symbolism in that.

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